Add Tests for DEFAULT_FONTS_BASE64 Coverage in SVG Generator

[ChetanSenta]

Description

Fixes #8325

Pillar

• 🎨 Pillar 1 — New Theme Design
• 📐 Pillar 2 — Geometric SVG Improvement
• 🕐 Pillar 3 — Timezone Logic Optimization
• 🛠️ Other (Bug fix, refactoring, docs)

Visual Preview

No visual change — pure test additions.

What this PR does

All 16 occurrences of process.env.NODE_ENV === 'test' ? <google-fonts-url> : DEFAULT_FONTS_BASE64
in lib/svg/generator.ts mean DEFAULT_FONTS_BASE64 (the real,
production font-embedding constant in lib/svg/fonts.ts) is never
actually rendered by any existing test, since Vitest sets
NODE_ENV=test. Added lib/svg/fonts.test.ts: direct structural checks
on the constant itself (bypassing the branch entirely), plus one test
that temporarily overrides NODE_ENV to confirm a real generator
function actually embeds the real font CSS in production.

Checklist before requesting a review:

• I have read the CONTRIBUTING.md file.
• I have tested these changes locally.
• I have run npm run format and npm run lint locally and resolved all errors.
• My commits follow the Conventional Commits format.
• I have made sure that I have only one commit to merge in this PR.

[retenta-bot]

This pull request addresses the lack of test coverage for the DEFAULT_FONTS_BASE64 constant in the SVG generator. It introduces tests that directly check the constant and also validate the font embedding functionality in a production-like environment. This aligns with our previous decisions to enhance testing practices, such as adding unit tests for timezone normalization and implementing visual regression testing for SVG generators. Thank you for your contribution, and I look forward to your updates!

[github-actions]

📦 Next.js Bundle Size Report (Gzipped Sizes)

✨ No significant bundle size changes detected.

📊 Summary of Totals

Category	PR Size	Base Size	Difference
Total JS	4052.50 KB	4052.50 KB	0 B
Total CSS	338.94 KB	338.94 KB	0 B

[Aamod007]

Clean test additions for font coverage in the SVG generator. CI pending — once green, good to merge.

Labels: level:beginner (1 file), quality:clean, type:testing, mentor:Aamod007

[Aamod007]

Re-reviewing after noting the only CI failure is Vercel authorization (not code-related). All other checks (Format · Lint · Typecheck · Test, Production Build, CodeQL) pass. Approving — the Vercel deploy auth is a repo-level config issue, not a code problem.